In short, for your own sake, DON'T BUY THESE!
I try to stay as objective as possible in this and don't have any feelings against Brainwavz. It deeply saddens me to write a negative review on these because I really looked forward to them and have never written one before. If they sold the ones I got (M5) for 20$ at the grocery store, it would still be an insult to every customer. More on that later. (The other Headphones in this drop seem to be of very questionable quality as well from what I could read here and on other sites)
I got the M5 and have to say they are absolutely terrible in almost every single way, even compared to some 5$ headphones. Even tho you can equalize them so sound somewhat acceptable, out of the box they trade blows with the crap headphones you get for free on tourbusses. And I do not exaggerate by saying that. I don't even want to.
To describe the sound, bass is basically non existent. Although it can partially be brought back with equalizing, it's still wont get very low and doesnt't seem precise. The unacceptable part about these headphone's sound however is the absurd mids to mid-highs. Don't get me wrong, I very much like treble, but this isn't clear treble in any way, this is a dying kitten screaming for help. I completely turned down the frequencies between 3.5k kHz and 8k kHz and its still unacceptable. Not only because the frequencies are still to loud, but also because the high mids to the mid highs are in no way precise and still sound resonating and overpower everything else. Everything above like 10k sounds very inconsistent to my ears as if they struggle to reach it. Again, most headphones i got for free have a more pleasant sound.
I bought them because I just needed some relatively cheap headphones I can use for very short trips. I did not expect audiophile headphones for 25$ without shipping, however literally nobody I let test them managed to listen to them over even over shorter periods at normal volumes. I didn't tell them that I find them to be unbelievably bad before, I told them they are good to see what their reaction was. They still told me that the headphones are terrible. Most of them normally don't care about audio at all and even call me overly sensitive.
I think I don't need to further explain why the statements "Clear & Balanced Sound" and "Accurate Sound Reproduction" on the outside of the box are straight up lies, at least with the example I got. But even after some investigation I found that this very likely also applies to the other Brainwavz headphones you get in this drop.
The housing of them is OK, the cable seems rather thin but acceptable and on the first look the plastic around the plug seems above average and sturdy but is let down again by them making phones freak to when I plug them in (Skipping songs, activating voicecontrol, etc).
There are positive reviews about these online, which I don't doubt were accurate at that time, but from what I could read they significantly dropped the production quality and were good headphones back then. Starting with the end of 2016, they just don't seem to be good anymore and I am very sorry to say that. Again, I don't exaggerate, don't' hate Brainwavz and am not some radical fan that rants to destroy some other companies reputation. If they revert back to how they have possibly been I would give them another chance. I am just stating my observations.
All of that would be OK if they were like 5$, but the absolute worst part about these is that how much the MSRP of these is, and even how much I payed for them on here. It is an absolute insolence to want 50$ for them normally and even the like 30$ I payed for them with shipping here on Massdrop is unbelievable. I offered them to some non-audiophile friends of mine and they didn't want them for free and honestly I don't want anyone to have to live with these anyways. I really wanted to give them a chance, I "burned them in" for a few hours and also I listened to them from multiple different sources with the same overwhelmingly bad result every time.